Scrolling Through Changes

The first request to the Changes API returns the earliest changes. To continue reading a chronological list of changes, grab the next_token value and add it to your next query using ?since=[next_token].

This process is repeated until there are no further changes. When all changes are read, the last request returns the same next_token passed in as a parameter, along with an empty set of changes:

{"next_token":"13835315192676945401741312","changes":[]}

Using a Date to Read Changes

You may also want to jump into the middle of the change feed based on a time. This is possible by using a UTC date with the since parameter:

curl https://data-axle.com/api/1/places/changes?since=2014-12-24

Additions, Removals and Updates

Most changes are updates to existing records. However, some changes are for completely new records and others are for the removal of records.

The type of change is described by the type field, which can be one of three values:

"addition" - The record is new to the feed.

"removal" - The record is exiting the feed.

"update" - The record is already in the feed and has a field change.

Additions

Additions can happen for two reasons:

A new record is added to the Infogroup database.

An existing record is modified to match the changes being subscribed to. For example, if your account only receives records in the state of California, and an existing record has a state change from Arizona to California, it will appear as an "addition":

Removals

Removals can happen for two reasons:

An existing record is invalidated in the Infogroup database. Reasons for this can include closed businesses and duplicate record detection.

An existing record is modified to no longer match the changes being subscribed to. For example, if your account only receives records in the state of California, and an existing record has a state change from California to Arizona, it will appear as an "removal":

Attribute Updates, Fills and Removals

The current section of the record shows the record after the change was applied, including all attributes. The previous section shows an abbreviated record which highlights changes made to the record. By comparing the values in the current and previous sections, you can determine which attributes changed and how they were changed.

An attribute which has changed from one value to another is shown as follows:

This shows that the name was changed from "Brooklyn Pizza" to "New York Pizza".

If a field's value was added where the value didn't exist before, this is represented by a null JSON value in the previous section. The following example would show that a suite number was added to the record where there was no entry for the suite number before: